In another window, run `nc -l 8000` (mac) or `nc -l -p 8000` (linux) to listen on port 8000. Then run this class with the otel java agent.

HttpUrlConnectionCheck.java

package io.opentelemetry.javaagent;

import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.concurrent.TimeUnit;

import static java.nio.charset.StandardCharsets.UTF_8;

public class HttpUrlConnectionCheck {

  private HttpUrlConnectionCheck() {}

  public static void main(String[] args) throws Exception {

    while (true) {
      doPost();
      TimeUnit.SECONDS.sleep(5);
    }
  }

  private static void doPost() throws Exception {
//    URL url = new URL("http://example.com");
    URL url = new URL("http://localhost:8000");
    System.out.println("Opening connection...");
    HttpURLConnection conn = (HttpURLConnection) url.openConnection();
    conn.setDoOutput(true);
    conn.setRequestMethod("POST");
    OutputStream out = conn.getOutputStream();
    OutputStreamWriter writer = new OutputStreamWriter(out, UTF_8);
    writer.write("this is a test\n\n");
    writer.flush();
    writer.close();
    out.close();
    System.out.println("All done.");
  }
}